Ore-roasting furnace.



PATENT Enron.

JOHN ROGER, OF DENVER, COLORADO.

O RE-ROASTING FURNACE.

SPECIFICATION forming part of Letters Patent N 0. 677,701, dated July 2,1901.

Application filed February 12, 1901. Serial No. 47,088. (No model.)

To aZZ whom, it may concern.-

Be it known that I, JOHN ROGER, a subject of the King of Great Britain,residing at Denver, in the county of Arapahoe and State of Colorado,have invented new and useful I111- provements in Ore-Roasting Furnaces,of which the following is a specification.

This invention relates to ore-roasting f urnaces, and it includescertain fundamental features hereinafter set forth.

The ordinary manner now employed for delivering ore to aroasting-furnace is to drop the ore from the top arch onto the hearth orto supply it from a point above and at one side of the hearth. These aredecidedly objectionable, as during the descent of the ore it crosses thedraft of the furnace, and as the draft is always high much of the finematerial is caught thereby and is carried away, thereby causing a greatloss. By my improved furnace, however, these losses are wholly avoided.My ore-feeding means are situated below or. substantially below thehearth and deliver the ore upward into the furnace for treatmentthereby, and this being the case there is no possibility of any part ofthe moving mass coming in contact with the draft, so that no waste inore during its supply to the hearth can possibly ensue.

The ore-underfeeding mechanism is exceedingly simple and is capable ofmaintaining an adequate supply of the ore, and it also evenlydistributes the same along the hearth, and while the invention is in nowise limited to any particular kind of device or apparatus for feedingthe ore onto the hearth from below the same I find a spiral conveyer orscrew advantageously adapted to this function, the conveyor or screwtapering toward one end thereof, so that the reduced end thereof beingunable to carry the ore forward as fast as it is fed forward by thelarger end of said screw the ore will be naturally elevated along thelength of the screw, being simultaneously fed to the hearth anddistributed across the same.

The invention is represented in one embodiment thereof in theaccompanying drawings, forming a part of this specification, wherein-'-Figure 1 is a cross-sectionalelevation of an ore-roasting furnaceinvolving my invention. Fig. 2 is a sectional plan View of said furnace.

Fig. 3 is an enlarged sectional elevation of one end of the feed-screw.Fig. 4 1s an ele- .vation of the screw, showing a difierent formthereof.

In the drawings I have shown a portion of a familiar type ofore-roasting furnace in which my underfeeding mechanism is incorporatedand will now briefly describe the same, it being understood, of course,that the improvements may be employed with equal facility in other kindsof ore roasting f urnaces.

highly advantageous for securing the desired functions. That end of thefeed-screw which receives the ore is the larger, and said screwgradually tapers from said end to the oppo site one. The feed-screw islocated in a casing or boxing, as 16-, substantially V-shaped incross-section and having oppositely-disposed lateral flanges, as 17,along its upper edges, which may be suitably embodied in or secured tothe hearth 13. The casing 16, and hence the feed-screw inclosed thereby,lies transversely of the furnace, and by reason of the shape of thecasing an elongated dischargeopening 15 is formed upon the top or upperside of the same, through which the ore is positively fed anddistributed. The front end of the casing is flanged, as at 18, and ashelf or bracket, as 19, is connected to said flange and supports aboxing or bearing for receiving one end of the feed-screw shaft and avertical shaft, as 20. The opposite end of said feed-screw shaft has awear-piece 21, engaged by a screw, as 22, carried by the bearing 23,bolted or otherwise secured to the rear end of the casing 16, said rearend being flanged, as at 24, to fit within a squared opening inthe'brickwork of the furnace, suitable fastening devices extendingthrough said flange into the brickwork. The inner end of the casing 16is covered by a cap or plate, as 25,having an 0pening-,as 26,throughwhich the ore can pass, the ore gravitating from a hopper, as 27, ofsuitable size and supported in some convenient manner. The plate haslugs 25 on its under side, adapted to fit snugly against the inner faceof the trough-shaped casing 16. A chute orsupply-tube, as 28, dependsfrom said hopper, and its delivery end is in proximity to and over thechargingopening 26. The crushed ore therefore descends from the hopper27 into the chute 28, from which it is discharged into the troughshapedcasing 16, where it is met by the tapered feed-screw 15, and as thelatter rotates it advances the ore laterally of the furmace and at thesame time lifts it onto the hearth 13.

Any suitable mechanism may be employed for driving the underfeed-screw,a system of intermeshing gears being shown for this purpose connected tothe shafts hereinbefore mentioned.

The horizontal feed-screw shaft carries a bevel-gear, as 15", meshingwith a coacting bevel-gear 20 on the lower end of the vertical shaft 20,while said shaft 20 carries at its upper end a bevel-gear, as 20",meshing with a cooperating gear 30 on the horizontal andsuitably-supported line-shaft 30, the latter carrying a driving member,as the pulley 31. Said pulley may be connected by a belt (not shown)with a motor or other power-furnishing device. When the shaft 30 isrotated, the feed-screw 15 will be through the agency of theintermediate parts rotated, so as to supply the ore to the hearth. Theore is supplied in some suitable manner to the hopper 27,,from whence itpasses to the communisaid chute.

eating chute 28, gravitating from the latter onto the feed-screw 15, theflow of the mass through the chute being regulated by a handvalve, as35, of the slide type, intersecting The ore will be taken by therotating feed-screw and advanced transversely or crosswise of thefurnace and at the same time caused to rise and pass through the longitudinal opening 16' in the top of the casing I 16. As the feed-screwis of progressively-decreasing crosssectional area from its front'to itsrear end, the reduced or smaller part thereof will be insufiicient tocarry the ore forward as fast as it is delivered from the larger part ofsaid feed-screw, so that the ore is from the chute 28.

As shown in Fig. 4, the thread of the screw maybe omitted at intervals,thereby to reduce friction on the gearing, besides securing an evendistribution if an insufficient amount of material is fed.

Having described the invention, I claim- 1. In an ore-roasting furnace,a roastinghearth and a feed-screw located below and coextensive with thehearth transversely thereof, said feed-screw being tapered from itsorereceiving end toward its opposite end.

2. In an ore-roasting furnace, a roastinghearth, and a feed devicelocated below the hearth and coextensive with the same transverselythereof, constructed and arranged to elevate the ore onto said hearthand simultaneously to distribute the same across said hearth.

3. In an ore-roasting furnace, a roastinghearth and a feed-screw locatedbelow the hearth having portions of its thread removed, and ofprogressively-decreasin g taper from its ore-receiving end to theopposite end thereof.

In testimony whereof I have hereunto set my hand in presence of twosubscribing witnesses.

JOHN ROGER.

Witnesses:

A. B. KENNEDY, ALFRED DUNN.

